Researchers have discovered a method to enhance the durability of a specific type of plastic, making it less prone to releasing harmful microplastics.
Researchers have discovered a method to enhance the durability of a specific type of plastic, making it less prone to releasing harmful microplastics.
The research focused on a reliable approach to bond chemical additives to polyvinyl chloride (PVC).
PVC is commonly found in a variety of products such as toys, building materials, and medical packaging, making it the third most utilized plastic globally. Despite its popularity, pure PVC tends to be fragile and sensitive to heat, prompting manufacturers to stabilize it with additional chemicals before use.
However, these stabilizing additives, also known as plasticizers, only provide a temporary solution. Over time, these substances can leach out, leading the plastic to break down into potentially harmful compounds and microplastics. A research team headed by Christo Sevov, an associate professor of chemistry and biochemistry at The Ohio State University, has now found a way to apply electricity to securely bond these chemical additives to PVC, reducing unwanted reactions.
“Our technique differs from traditional methods, as it involves chemically attaching the plasticizer directly to PVC rather than merely mixing them together,” Sevov explained.
This modification of PVC molecules enhances their durability and resistance to chemical changes, ultimately producing materials with improved characteristics.
“We’re excited about the level of control we have over altering PVC properties,” Sevov stated. “This represents the first step towards intentionally changing PVC’s attributes, be it to make it harder, stretchier, or softer.”
The team faced some obstacles; many synthetic polymer modifications fail because the chemical reactions are typically designed for small molecules rather than larger ones like pure PVC. The researchers tackled this issue by refining their catalyst and, through extensive experimentation, managed to navigate the challenges of working with larger molecules.
The findings have been published in the journal Chem.
In addition to advancing organic chemistry, this team’s research has significant environmental implications. Slowing down the degradation of plastics can significantly reduce the release of microplastics—tiny plastic fragments—into the environment.
Currently, it is understood that these particles pollute our air, water, and food supply, posing risks to both human health and wildlife. The average individual is estimated to ingest between 78,000 and 211,000 microplastic particles each year.
As scientists gain insight into the long-term effects of microplastics on the planet, organic chemists are racing to find solutions to eliminate them from daily life, Sevov noted.
“Many chemists are redirecting their focus toward large molecules to develop innovative methods for upcycling, recycling, and modifying established polymers,” he remarked. For instance, recycling PVC can further weaken the material, as high temperatures are required to transform plastic into different forms, making the process inefficient.
In contrast, Sevov’s method allows for significantly more reuse of the material before it begins to degrade, thereby enhancing its lifespan and reusability, he explained.
Looking ahead, greater control over which materials are safe for consumers will be achievable once strategies to mitigate PVC degradation can be efficiently scaled up. The study highlights that their approach is currently the only viable method for such commercial PVC modifications.
“There’s no more effective way to accomplish this on a scale necessary for commercial PVC alterations, as it is a massive undertaking,” Sevov stated. “Although there’s still much work ahead to fully address the microplastic issue, we’ve established a solid foundation for moving forward.”
Other co-authors from Ohio State include Jordan L.S. Zackasee, Valmuri Srivardhan, Blaise L. Truesdell, and Elizabeth J. Vrana. This research received support from the Department of Energy’s Early Career Research Program.